Selling a house and going full time should not adversely affect your credit.
A good place to check and monitor your credit for free;
https://www.creditkarma.com/You can play with different hypothetical changes and see the effect on your score.
The site for federally mandated free credit reports (does not include FICO score);
https://www.annualcreditreport.com/index.actionI recommend that everyone should place a credit freeze on your account at each of the three reporting agencies. At most it will cost you $30 depending on state of residence. It is the only way to be guaranteed to prevent id theft and can easily be thawed at any time. Monitoring services are a waste of money and not worth having even if free. For info;
http://www.clarkhoward.com/credit-freeze-and-thaw-guide